Please use the {;}Code button when posting code.

My primary goal is to meet the stated business requirements for the code, which I don't believe your code does.  You will list the "truePct" for even a single...

Maybe this?:

SELECT  poll_id ,start_date,end_date,
candidate_name, sample_size,
(select avg(pp2.pct) from [president_polls] pp2 
    where pp2.state = pp.state and pp2.poll_id = pp.poll_id 
   ...

Here is the beginning of a solution.  It uses James F. Allen's (no relation) Interval Algebra:  https://en.wikipedia.org/wiki/Allen%27s_interval_algebra.

The amount used from each bin depends on the relation between the purchases...

• This reply was modified 2 years ago by drew.allen.

The endpoints of the window can be specified as any of the following in order:

• UNBOUNDED PRECEDING
• <n> PRECEDING
• CURRENT ROW
• <n> FOLLOWING
• UNBOUNDED FOLLOWING

NOTE: The first endpoint must precede...

You should always check your scripts before posting them on the Internet.  You have an extra comma in your INSERT clause.  You should also make sure that others don't need...

Presumably, the ID field is the primary/unique key, so adding DISTINCT will not change the results,...

I think you need to include the leading zero, since this is a string, not an integer.

select ‘Amount’ as Amount, [0] ,[1] ,[2] ,[2] ,[3] ,[4] ,[5]...

You didn't provide sample data and expected results.

This is my best guess:

WITH BRE AS
(
    SELECT Id, WOCode, Site, Section, CompletionDate
    ...

This solution gives similar results, but performs faster, because there are fewer reads.

SELECT f.createdate, f.holiday, f.holidaydate, f.holidayall, h.holiday, h.holidaydate
     , MAX(h.holiday) OVER(ORDER BY...

The STRING_SPLIT() function was introduced in SQL 2016.  It's not as powerful as the solution Johan is pointing to, but it should suffice for your purposes.

Drew

You're missing sample data and expected results.

It looks like a partial rollup.  Without sample data and expected results, I can only hazard a guess.  The following should be close-ish.

J. Drew Allen

Business Intelligence Analyst

Philadelphia, PA